联络通道原状冻土无侧限抗压强度试验研究  

Experimental study on unconfined compression strength of undisturbed frozen soil around the connection passage

作　　者：郭胜远 黄建 曹咏娜 韩继勇 贾德华[2] GUO Shengyuan;HUANG Jian;CAO Yongna;HAN Jiyong;JIA Dehua(Jinan Traffic Engineering Quality and Safety Center,Jinan Shandong 250014,China;Academy of Railway Sciences(Beijing)Engineering Consult Co.,Ltd.,Beijing 100081,China)

机构地区：[1]济南市交通工程质量与安全中心,山东济南250014 [2]铁科院(北京)工程咨询有限公司,北京100081

出　　处：《现代城市轨道交通》2024年第12期118-121,共4页Modern Urban Transit

摘　　要：某市地铁区间联络通道采取冻结法施工,冻结区主要含粉质黏土和细沙。为保障冻结开挖施工过程中的安全,验证冻土帷幕强度是否满足施工要求,对该冻结区域进行原状冻土取样,并制作冻土试样进行无侧限抗压强度试验,对冻土强度以及破坏方式进行分析。结果表明,细沙冻土试样平均抗压强度为3.40 MPa,破坏表现为脆性,其中失去抗压能力有2种方式,包括结构破坏,以及受外界影响,冻土中的冰融化使细沙解体而失去承载能力。粉质黏土冻土试样平均抗压强度为0.67 MPa,破坏表现为塑性,主要是受外界影响,冻结融化导致冻土的抗压承载能力下降。最后通过对试验结果和现象分析,提出冻结施工合理化建议,以保障冻结施工过程的安全,为类似冻结工程提供一定参考和借鉴。The connection passage of a metro section in a city is constructed by using the freezing method,and the frozen area mainly contains silty clay and fine sand.To ensure the safety of frozen excavation construction process and verify whether the strength of frozen soil wall meets the construction requirements,undisturbed frozen soil samples were taken from the frozen area,and unconfined compression strength tests were conducted on the samples to analyze the strength and failure mode.The results showed that the average compression strength of the frozen soil samples with fine sand was 3.40 MPa on brittle failure.There were two ways to lose its compressive stability,including structural failure and external factors causing melting in the frozen soil,which led to the disintegration of fine sand and the loss its compressive stability;The average compression strength of the silty clay frozen soil sample is 0.67 MPa on plasticity failure,mainly due to the influence of external factors,such as freezing and thawing,which leads to a decrease in the compressive stability of frozen soil.Finally,based on the results and phenomena generated from the experiment,reasonable suggestions for frozen construction are proposed to ensure the safety of the frozen construction process and provide some reference for similar frozen projects.

关 键 词：地铁 联络通道 冻结法施工 原状冻土 抗压强度 

分 类 号：U231.3[交通运输工程—道路与铁道工程]